Fix nonsensical bitcoin-cli -norpcwallet behavior

Treat specifying -norpcwallet the same as not specifying any -rpcwallet option,
instead of treating it like -rpcwallet=0 with 0 as the wallet name.

This restores previous behavior before 7430775
from bitcoin/bitcoin#18594, which inadvertently changed
it.

Author: ryanofsky

src/bitcoin-cli.cpp

@@ -110,6 +110,13 @@ static void SetupCliArgs(ArgsManager& argsman)
     argsman.AddArg("-stdinwalletpassphrase", "Read wallet passphrase from standard input as a single line. When combined with -stdin, the first line from standard input is used for the wallet passphrase.", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
 }
 
+std::optional<std::string> RpcWalletName(const ArgsManager& args)
+{
+    // Check IsArgNegated to return nullopt instead of "0" if -norpcwallet is specified
+    if (args.IsArgNegated("-rpcwallet")) return std::nullopt;
+    return args.GetArg("-rpcwallet");
+}
+
 /** libevent event log callback */
 static void libevent_log_cb(int severity, const char *msg)
 {
@@ -1183,10 +1190,8 @@ static void ParseGetInfoResult(UniValue& result)
  */
 static UniValue GetNewAddress()
 {
-    std::optional<std::string> wallet_name{};
-    if (gArgs.IsArgSet("-rpcwallet")) wallet_name = gArgs.GetArg("-rpcwallet", "");
     DefaultRequestHandler rh;
-    return ConnectAndCallRPC(&rh, "getnewaddress", /* args=*/{}, wallet_name);
+    return ConnectAndCallRPC(&rh, "getnewaddress", /* args=*/{}, RpcWalletName(gArgs));
 }
 
 /**
@@ -1291,16 +1296,15 @@ static int CommandLineRPC(int argc, char *argv[])
         }
         if (nRet == 0) {
             // Perform RPC call
-            std::optional<std::string> wallet_name{};
-            if (gArgs.IsArgSet("-rpcwallet")) wallet_name = gArgs.GetArg("-rpcwallet", "");
+            const std::optional<std::string> wallet_name{RpcWalletName(gArgs)};
             const UniValue reply = ConnectAndCallRPC(rh.get(), method, args, wallet_name);
 
             // Parse reply
             UniValue result = reply.find_value("result");
             const UniValue& error = reply.find_value("error");
             if (error.isNull()) {
                 if (gArgs.GetBoolArg("-getinfo", false)) {
-                    if (!gArgs.IsArgSet("-rpcwallet")) {
+                    if (!wallet_name) {
                         GetWalletBalances(result); // fetch multiwallet balances and append to result
                     }
                     ParseGetInfoResult(result);

test/functional/interface_bitcoin_cli.py

@@ -279,6 +279,10 @@ def run_test(self):
             assert_equal(cli_get_info['Wallet'], wallets[1])
             assert_equal(Decimal(cli_get_info['Balance']), amounts[1])
 
+            self.log.info("Test -getinfo -norpcwallet returns the same as -getinfo")
+            # Previously there was a bug where -norpcwallet was treated like -rpcwallet=0
+            assert_equal(self.nodes[0].cli('-getinfo', "-norpcwallet").send_cli(), cli_get_info_string)
+
             self.log.info("Test -getinfo with -rpcwallet=remaining-non-default-wallet returns only its balance")
             cli_get_info_string = self.nodes[0].cli('-getinfo', rpcwallet2).send_cli()
             cli_get_info = cli_get_info_string_to_dict(cli_get_info_string)